drivers/hwmon/max1619.c

   1 /*
   2  * max1619.c - Part of lm_sensors, Linux kernel modules for hardware
   3  *             monitoring
   4  * Copyright (C) 2003-2004 Alexey Fisher <fishor@mail.ru>
   5  *                         Jean Delvare <khali@linux-fr.org>
   6  *
   7  * Based on the lm90 driver. The MAX1619 is a sensor chip made by Maxim.
   8  * It reports up to two temperatures (its own plus up to
   9  * one external one). Complete datasheet can be
  10  * obtained from Maxim's website at:
  11  *   http://pdfserv.maxim-ic.com/en/ds/MAX1619.pdf
  12  *
  13  * This program is free software; you can redistribute it and/or modify
  14  * it under the terms of the GNU General Public License as published by
  15  * the Free Software Foundation; either version 2 of the License, or
  16  * (at your option) any later version.
  17  *
  18  * This program is distributed in the hope that it will be useful,
  19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21  * GNU General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU General Public License
  24  * along with this program; if not, write to the Free Software
  25  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  26  */
  27
  28
  29 #include <linux/module.h>
  30 #include <linux/init.h>
  31 #include <linux/slab.h>
  32 #include <linux/jiffies.h>
  33 #include <linux/i2c.h>
  34 #include <linux/hwmon.h>
  35 #include <linux/hwmon-sysfs.h>
  36 #include <linux/err.h>
  37 #include <linux/mutex.h>
  38 #include <linux/sysfs.h>
  39
  40 static const unsigned short normal_i2c[] = {
  41         0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x4c, 0x4d, 0x4e, I2C_CLIENT_END };
  42
  43 /*
  44  * Insmod parameters
  45  */
  46
  47 I2C_CLIENT_INSMOD_1(max1619);
  48
  49 /*
  50  * The MAX1619 registers
  51  */
  52
  53 #define MAX1619_REG_R_MAN_ID            0xFE
  54 #define MAX1619_REG_R_CHIP_ID           0xFF
  55 #define MAX1619_REG_R_CONFIG            0x03
  56 #define MAX1619_REG_W_CONFIG            0x09
  57 #define MAX1619_REG_R_CONVRATE          0x04
  58 #define MAX1619_REG_W_CONVRATE          0x0A
  59 #define MAX1619_REG_R_STATUS            0x02
  60 #define MAX1619_REG_R_LOCAL_TEMP        0x00
  61 #define MAX1619_REG_R_REMOTE_TEMP       0x01
  62 #define MAX1619_REG_R_REMOTE_HIGH       0x07
  63 #define MAX1619_REG_W_REMOTE_HIGH       0x0D
  64 #define MAX1619_REG_R_REMOTE_LOW        0x08
  65 #define MAX1619_REG_W_REMOTE_LOW        0x0E
  66 #define MAX1619_REG_R_REMOTE_CRIT       0x10
  67 #define MAX1619_REG_W_REMOTE_CRIT       0x12
  68 #define MAX1619_REG_R_TCRIT_HYST        0x11
  69 #define MAX1619_REG_W_TCRIT_HYST        0x13
  70
  71 /*
  72  * Conversions and various macros
  73  */
  74
  75 #define TEMP_FROM_REG(val)      ((val & 0x80 ? val-0x100 : val) * 1000)
  76 #define TEMP_TO_REG(val)        ((val < 0 ? val+0x100*1000 : val) / 1000)
  77
  78 /*
  79  * Functions declaration
  80  */
  81
  82 static int max1619_probe(struct i2c_client *client,
  83                          const struct i2c_device_id *id);
  84 static int max1619_detect(struct i2c_client *client, int kind,
  85                           struct i2c_board_info *info);
  86 static void max1619_init_client(struct i2c_client *client);
  87 static int max1619_remove(struct i2c_client *client);
  88 static struct max1619_data *max1619_update_device(struct device *dev);
  89
  90 /*
  91  * Driver data (common to all clients)
  92  */
  93
  94 static const struct i2c_device_id max1619_id[] = {
  95         { "max1619", max1619 },
  96         { }
  97 };
  98 MODULE_DEVICE_TABLE(i2c, max1619_id);
  99
 100 static struct i2c_driver max1619_driver = {
 101         .class          = I2C_CLASS_HWMON,
 102         .driver = {
 103                 .name   = "max1619",
 104         },
 105         .probe          = max1619_probe,
 106         .remove         = max1619_remove,
 107         .id_table       = max1619_id,
 108         .detect         = max1619_detect,
 109         .address_data   = &addr_data,
 110 };
 111
 112 /*
 113  * Client data (each client gets its own)
 114  */
 115
 116 struct max1619_data {
 117         struct device *hwmon_dev;
 118         struct mutex update_lock;
 119         char valid; /* zero until following fields are valid */
 120         unsigned long last_updated; /* in jiffies */
 121
 122         /* registers values */
 123         u8 temp_input1; /* local */
 124         u8 temp_input2, temp_low2, temp_high2; /* remote */
 125         u8 temp_crit2;
 126         u8 temp_hyst2;
 127         u8 alarms;
 128 };
 129
 130 /*
 131  * Sysfs stuff
 132  */
 133
 134 #define show_temp(value) \
 135 static ssize_t show_##value(struct device *dev, struct device_attribute *attr, char *buf) \
 136 { \
 137         struct max1619_data *data = max1619_update_device(dev); \
 138         return sprintf(buf, "%d\n", TEMP_FROM_REG(data->value)); \
 139 }
 140 show_temp(temp_input1);
 141 show_temp(temp_input2);
 142 show_temp(temp_low2);
 143 show_temp(temp_high2);
 144 show_temp(temp_crit2);
 145 show_temp(temp_hyst2);
 146
 147 #define set_temp2(value, reg) \
 148 static ssize_t set_##value(struct device *dev, struct device_attribute *attr, const char *buf, \
 149         size_t count) \
 150 { \
 151         struct i2c_client *client = to_i2c_client(dev); \
 152         struct max1619_data *data = i2c_get_clientdata(client); \
 153         long val = simple_strtol(buf, NULL, 10); \
 154  \
 155         mutex_lock(&data->update_lock); \
 156         data->value = TEMP_TO_REG(val); \
 157         i2c_smbus_write_byte_data(client, reg, data->value); \
 158         mutex_unlock(&data->update_lock); \
 159         return count; \
 160 }
 161
 162 set_temp2(temp_low2, MAX1619_REG_W_REMOTE_LOW);
 163 set_temp2(temp_high2, MAX1619_REG_W_REMOTE_HIGH);
 164 set_temp2(temp_crit2, MAX1619_REG_W_REMOTE_CRIT);
 165 set_temp2(temp_hyst2, MAX1619_REG_W_TCRIT_HYST);
 166
 167 static ssize_t show_alarms(struct device *dev, struct device_attribute *attr, char *buf)
 168 {
 169         struct max1619_data *data = max1619_update_device(dev);
 170         return sprintf(buf, "%d\n", data->alarms);
 171 }
 172
 173 static ssize_t show_alarm(struct device *dev, struct device_attribute *attr,
 174                           char *buf)
 175 {
 176         int bitnr = to_sensor_dev_attr(attr)->index;
 177         struct max1619_data *data = max1619_update_device(dev);
 178         return sprintf(buf, "%d\n", (data->alarms >> bitnr) & 1);
 179 }
 180
 181 static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp_input1, NULL);
 182 static DEVICE_ATTR(temp2_input, S_IRUGO, show_temp_input2, NULL);
 183 static DEVICE_ATTR(temp2_min, S_IWUSR | S_IRUGO, show_temp_low2,
 184         set_temp_low2);
 185 static DEVICE_ATTR(temp2_max, S_IWUSR | S_IRUGO, show_temp_high2,
 186         set_temp_high2);
 187 static DEVICE_ATTR(temp2_crit, S_IWUSR | S_IRUGO, show_temp_crit2,
 188         set_temp_crit2);
 189 static DEVICE_ATTR(temp2_crit_hyst, S_IWUSR | S_IRUGO, show_temp_hyst2,
 190         set_temp_hyst2);
 191 static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
 192 static SENSOR_DEVICE_ATTR(temp2_crit_alarm, S_IRUGO, show_alarm, NULL, 1);
 193 static SENSOR_DEVICE_ATTR(temp2_fault, S_IRUGO, show_alarm, NULL, 2);
 194 static SENSOR_DEVICE_ATTR(temp2_min_alarm, S_IRUGO, show_alarm, NULL, 3);
 195 static SENSOR_DEVICE_ATTR(temp2_max_alarm, S_IRUGO, show_alarm, NULL, 4);
 196
 197 static struct attribute *max1619_attributes[] = {
 198         &dev_attr_temp1_input.attr,
 199         &dev_attr_temp2_input.attr,
 200         &dev_attr_temp2_min.attr,
 201         &dev_attr_temp2_max.attr,
 202         &dev_attr_temp2_crit.attr,
 203         &dev_attr_temp2_crit_hyst.attr,
 204
 205         &dev_attr_alarms.attr,
 206         &sensor_dev_attr_temp2_crit_alarm.dev_attr.attr,
 207         &sensor_dev_attr_temp2_fault.dev_attr.attr,
 208         &sensor_dev_attr_temp2_min_alarm.dev_attr.attr,
 209         &sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
 210         NULL
 211 };
 212
 213 static const struct attribute_group max1619_group = {
 214         .attrs = max1619_attributes,
 215 };
 216
 217 /*
 218  * Real code
 219  */
 220
 221 /* Return 0 if detection is successful, -ENODEV otherwise */
 222 static int max1619_detect(struct i2c_client *new_client, int kind,
 223                           struct i2c_board_info *info)
 224 {
 225         struct i2c_adapter *adapter = new_client->adapter;
 226         u8 reg_config=0, reg_convrate=0, reg_status=0;
 227
 228         if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
 229                 return -ENODEV;
 230
 231         /*
 232          * Now we do the remaining detection. A negative kind means that
 233          * the driver was loaded with no force parameter (default), so we
 234          * must both detect and identify the chip. A zero kind means that
 235          * the driver was loaded with the force parameter, the detection
 236          * step shall be skipped. A positive kind means that the driver
 237          * was loaded with the force parameter and a given kind of chip is
 238          * requested, so both the detection and the identification steps
 239          * are skipped.
 240          */
 241         if (kind < 0) { /* detection */
 242                 reg_config = i2c_smbus_read_byte_data(new_client,
 243                               MAX1619_REG_R_CONFIG);
 244                 reg_convrate = i2c_smbus_read_byte_data(new_client,
 245                                MAX1619_REG_R_CONVRATE);
 246                 reg_status = i2c_smbus_read_byte_data(new_client,
 247                                 MAX1619_REG_R_STATUS);
 248                 if ((reg_config & 0x03) != 0x00
 249                  || reg_convrate > 0x07 || (reg_status & 0x61 ) !=0x00) {
 250                         dev_dbg(&adapter->dev,
 251                                 "MAX1619 detection failed at 0x%02x.\n",
 252                                 new_client->addr);
 253                         return -ENODEV;
 254                 }
 255         }
 256
 257         if (kind <= 0) { /* identification */
 258                 u8 man_id, chip_id;
 259
 260                 man_id = i2c_smbus_read_byte_data(new_client,
 261                          MAX1619_REG_R_MAN_ID);
 262                 chip_id = i2c_smbus_read_byte_data(new_client,
 263                           MAX1619_REG_R_CHIP_ID);
 264
 265                 if ((man_id == 0x4D) && (chip_id == 0x04))
 266                         kind = max1619;
 267
 268                 if (kind <= 0) { /* identification failed */
 269                         dev_info(&adapter->dev,
 270                             "Unsupported chip (man_id=0x%02X, "
 271                             "chip_id=0x%02X).\n", man_id, chip_id);
 272                         return -ENODEV;
 273                 }
 274         }
 275
 276         strlcpy(info->type, "max1619", I2C_NAME_SIZE);
 277
 278         return 0;
 279 }
 280
 281 static int max1619_probe(struct i2c_client *new_client,
 282                          const struct i2c_device_id *id)
 283 {
 284         struct max1619_data *data;
 285         int err;
 286
 287         data = kzalloc(sizeof(struct max1619_data), GFP_KERNEL);
 288         if (!data) {
 289                 err = -ENOMEM;
 290                 goto exit;
 291         }
 292
 293         i2c_set_clientdata(new_client, data);
 294         data->valid = 0;
 295         mutex_init(&data->update_lock);
 296
 297         /* Initialize the MAX1619 chip */
 298         max1619_init_client(new_client);
 299
 300         /* Register sysfs hooks */
 301         if ((err = sysfs_create_group(&new_client->dev.kobj, &max1619_group)))
 302                 goto exit_free;
 303
 304         data->hwmon_dev = hwmon_device_register(&new_client->dev);
 305         if (IS_ERR(data->hwmon_dev)) {
 306                 err = PTR_ERR(data->hwmon_dev);
 307                 goto exit_remove_files;
 308         }
 309
 310         return 0;
 311
 312 exit_remove_files:
 313         sysfs_remove_group(&new_client->dev.kobj, &max1619_group);
 314 exit_free:
 315         kfree(data);
 316 exit:
 317         return err;
 318 }
 319
 320 static void max1619_init_client(struct i2c_client *client)
 321 {
 322         u8 config;
 323
 324         /*
 325          * Start the conversions.
 326          */
 327         i2c_smbus_write_byte_data(client, MAX1619_REG_W_CONVRATE,
 328                                   5); /* 2 Hz */
 329         config = i2c_smbus_read_byte_data(client, MAX1619_REG_R_CONFIG);
 330         if (config & 0x40)
 331                 i2c_smbus_write_byte_data(client, MAX1619_REG_W_CONFIG,
 332                                           config & 0xBF); /* run */
 333 }
 334
 335 static int max1619_remove(struct i2c_client *client)
 336 {
 337         struct max1619_data *data = i2c_get_clientdata(client);
 338
 339         hwmon_device_unregister(data->hwmon_dev);
 340         sysfs_remove_group(&client->dev.kobj, &max1619_group);
 341
 342         kfree(data);
 343         return 0;
 344 }
 345
 346 static struct max1619_data *max1619_update_device(struct device *dev)
 347 {
 348         struct i2c_client *client = to_i2c_client(dev);
 349         struct max1619_data *data = i2c_get_clientdata(client);
 350
 351         mutex_lock(&data->update_lock);
 352
 353         if (time_after(jiffies, data->last_updated + HZ * 2) || !data->valid) {
 354                 dev_dbg(&client->dev, "Updating max1619 data.\n");
 355                 data->temp_input1 = i2c_smbus_read_byte_data(client,
 356                                         MAX1619_REG_R_LOCAL_TEMP);
 357                 data->temp_input2 = i2c_smbus_read_byte_data(client,
 358                                         MAX1619_REG_R_REMOTE_TEMP);
 359                 data->temp_high2 = i2c_smbus_read_byte_data(client,
 360                                         MAX1619_REG_R_REMOTE_HIGH);
 361                 data->temp_low2 = i2c_smbus_read_byte_data(client,
 362                                         MAX1619_REG_R_REMOTE_LOW);
 363                 data->temp_crit2 = i2c_smbus_read_byte_data(client,
 364                                         MAX1619_REG_R_REMOTE_CRIT);
 365                 data->temp_hyst2 = i2c_smbus_read_byte_data(client,
 366                                         MAX1619_REG_R_TCRIT_HYST);
 367                 data->alarms = i2c_smbus_read_byte_data(client,
 368                                         MAX1619_REG_R_STATUS);
 369
 370                 data->last_updated = jiffies;
 371                 data->valid = 1;
 372         }
 373
 374         mutex_unlock(&data->update_lock);
 375
 376         return data;
 377 }
 378
 379 static int __init sensors_max1619_init(void)
 380 {
 381         return i2c_add_driver(&max1619_driver);
 382 }
 383
 384 static void __exit sensors_max1619_exit(void)
 385 {
 386         i2c_del_driver(&max1619_driver);
 387 }
 388
 389 MODULE_AUTHOR("Alexey Fisher <fishor@mail.ru> and "
 390         "Jean Delvare <khali@linux-fr.org>");
 391 MODULE_DESCRIPTION("MAX1619 sensor driver");
 392 MODULE_LICENSE("GPL");
 393
 394 module_init(sensors_max1619_init);
 395 module_exit(sensors_max1619_exit);